The present invention concerns an internal combustion engine, and particularly an opposed piston engine. The invention also concerns an engine, designated a hydrocycle engine, for conversion of combustion energy from a column of gas between the opposed pistons to fluid displacement work.
Much recent attention has been focused upon the use of electronic controls to monitor the air-fuel mixture delivered to the engine, electronic fuel injectors to optimize the spray of fuel into the engine cylinder, and catalytic converters to reduce noxious emissions. Thus far, the focus of engine developers has been based upon standard internal combustion engine principles in which air-fuel mixture is ignited within a closed end cylinder. One recent example is represented by the two-cycle engine of the Orbital Engine Company of Perth, Australia.
It is also known that higher engine efficiency is achieved by direct conversion of combustion expansion energy into output work, as proven by gas turbine and jet aircraft engines. Internal combustion piston engines gain thermal efficiency by attaining combustion at much higher pressure and then expanding the gas over a much greater expansion ratio before exhaust. In some applications, the mechanical torque power from the crankshaft engine drives through fluid couplings or torque converters to hydrodynamically smooth clutch engagement without stalling the engine, and to provide some transmission ratio for starting heavy loads.
What is needed is an engine that combines the beneficial features of each of these engines without the limitations inherent in each. Such an engine would combine the direct conversion efficiency of a gas turbine with the high pressure expansion ratio of a piston engine, without the mechanical inertia and velocity variation of flywheel crank power. Such an engine would combine the convenient cycle control, starting, accessory drive and idle characteristics of the piston engine, with the instant direct conversion power efficiency of a turbine engine.